What is SOM (Serviceable Obtainable Market)?

SOM (serviceable obtainable market) is the share of your serviceable addressable market you can realistically win in a set planning period, given the team, channels, pricing and competition you actually have.

At a glance

• SOM is the smallest of three market sizes: TAM, then SAM, then SOM.
• TAM is total demand, SAM is the part your product can serve, and SOM is the part you can capture.
• Sources disagree on the time frame. Some planning guides use three to five years; others just say a defined period. Pick one and state it.
• SOM is the number that should tie to your sales plan, so it changes when headcount, channels or pricing change.

How to calculate SOM

Visible’s guide to bottom-up market sizing builds the number from customers, not from an industry report:

1. Define the segments you can serve.
2. Count the potential customers in each one.
3. Multiply by average revenue per customer to get revenue per segment.
4. Add the segments to get SAM.
5. Apply the share you can realistically win in the period to get SOM.

SOM = SAM × realistic share of SAM in the period

The share is the hard part. Ground it in what your team can actually work: how many accounts each rep can cover, your current win rate and the length of your sales cycle.

A SOM example

Example (illustrative): a fuel card company counts 12,000 small trucking fleets in the regions it serves, worth an average of $3,000 a year each. SAM is 12,000 × $3,000 = $36M. Its sales team can work about 2,400 fleets a year and wins one in five of those, so it can expect around 480 new customers.

• SAM: $36M
• Obtainable customers: 2,400 worked × 20% win rate = 480
• SOM: 480 × $3,000 = $1.44M a year, or 4% of SAM

Common SOM mistakes

• Picking a percentage. “We’ll take 1% of the market” isn’t a calculation. Build the share from capacity and conversion.
• Working back from the target. If SOM is set to match a board number, it stops telling you anything about the market.
• Top-down only. Visible’s guide notes that top-down sizing from industry reports is quicker but less reliable for niche or new markets.
• Ignoring competition. Accounts locked into a competitor on a multi-year contract aren’t obtainable this period.
• Never testing the assumptions. Visible suggests checking the estimate against secondary research and running small pilots to see real interest, pricing response and conversion before you plan around it.
• No time frame. A SOM without a period can’t be checked against results.

How SOM shows up in a revenue system

SOM becomes real when you can count the accounts behind it: a list of companies in each segment, with the contacts to reach them. Building and maintaining those account lists is the job of our datasets work, and the same counts feed coverage and territory planning. If the list behind your SOM is shorter than the plan assumes, the plan is the thing to change.

Terms that sit next to SOM

The accounts inside SOM are defined by your ICP and segmentation. Splitting SOM between reps is territory planning, and the pipeline you need to win it is measured as pipeline coverage.